API: Add support for type aliases

Previously all types are compound. This adds support for aliases,
so one can do things like:

typedef u32 interface_index;

or
typedef u8 ip4_address[4];

Change-Id: I0455cad0123fc88acb491d2a3ea2725426bdb246
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Klement Sekera <ksekera@cisco.com>

5 files changed, 87 insertions, 23 deletions

diff --git a/src/vpp-api/python/vpp_papi/vpp_papi.py b/src/vpp-api/python/vpp_papi/vpp_papi.py
index ca4b955fd07..bd2682f5b8f 100644
--- a/src/vpp-api/python/vpp_papi/vpp_papi.py
+++ b/src/vpp-api/python/vpp_papi/vpp_papi.py
@@ -27,7 +27,7 @@ import fnmatch
 import weakref
 import atexit
 from . vpp_serializer import VPPType, VPPEnumType, VPPUnionType, BaseTypes
-from . vpp_serializer import VPPMessage, vpp_get_type
+from . vpp_serializer import VPPMessage, vpp_get_type, VPPTypeAlias
 from . vpp_format import VPPFormat
 
 if sys.version[0] == '2':
@@ -102,13 +102,15 @@ class VPP(object):
         for t in api['types']:
             t[0] = 'vl_api_' + t[0] + '_t'
             types[t[0]] = {'type': 'type', 'data': t}
+        for t, v in api['aliases'].items():
+            types['vl_api_' + t + '_t'] = {'type': 'alias', 'data': v}
 
         i = 0
         while True:
             unresolved = {}
             for k, v in types.items():
                 t = v['data']
-                if not vpp_get_type(t[0]):
+                if not vpp_get_type(k):
                     if v['type'] == 'enum':
                         try:
                             VPPEnumType(t[0], t[1:])
@@ -124,6 +126,11 @@ class VPP(object):
                             VPPType(t[0], t[1:])
                         except ValueError:
                             unresolved[k] = v
+                    elif v['type'] == 'alias':
+                        try:
+                            VPPTypeAlias(k, t)
+                        except ValueError:
+                            unresolved[k] = v
             if len(unresolved) == 0:
                 break
             if i > 3:
diff --git a/src/vpp-api/python/vpp_papi/vpp_serializer.py b/src/vpp-api/python/vpp_papi/vpp_serializer.py
index bd0f73803da..a001cca565a 100644
--- a/src/vpp-api/python/vpp_papi/vpp_serializer.py
+++ b/src/vpp-api/python/vpp_papi/vpp_serializer.py
@@ -79,7 +79,7 @@ class FixedList_u8(object):
         self.packer = BaseTypes(field_type, num)
         self.size = self.packer.size
 
-    def pack(self, list, kwargs):
+    def pack(self, list, kwargs = None):
         """Packs a fixed length bytestring. Left-pads with zeros
         if input data is too short."""
         if not list:
@@ -277,6 +277,18 @@ class VPPUnionType(object):
         return self.tuple._make(r), maxsize
 
 
+def VPPTypeAlias(name, msgdef):
+    t = vpp_get_type(msgdef['type'])
+    if not t:
+        raise ValueError()
+    if 'length' in msgdef:
+        if msgdef['length'] == 0:
+            raise ValueError()
+        types[name] = FixedList(name, msgdef['type'], msgdef['length'])
+    else:
+        types[name] = t
+
+
 class VPPType(object):
     # Set everything up to be able to pack / unpack
     def __init__(self, name, msgdef):
diff --git a/src/vpp-api/vapi/vapi_c_gen.py b/src/vpp-api/vapi/vapi_c_gen.py
index eb1006d3a7e..9939bc0556c 100755
--- a/src/vpp-api/vapi/vapi_c_gen.py
+++ b/src/vpp-api/vapi/vapi_c_gen.py
@@ -5,15 +5,18 @@ import os
 import sys
 import logging
 from vapi_json_parser import Field, Struct, Enum, Union, Message, JsonParser,\
-    SimpleType, StructType
+    SimpleType, StructType, Alias
 
 
 class CField(Field):
+    def get_c_name(self):
+        return self.name
+
     def get_c_def(self):
         if self.len is not None:
-            return "%s %s[%d]" % (self.type.get_c_name(), self.name, self.len)
+            return "%s %s[%d];" % (self.type.get_c_name(), self.name, self.len)
         else:
-            return "%s %s" % (self.type.get_c_name(), self.name)
+            return "%s %s;" % (self.type.get_c_name(), self.name)
 
     def get_swap_to_be_code(self, struct, var):
         if self.len is not None:
@@ -95,12 +98,26 @@ class CField(Field):
         return result
 
 
+class CAlias(CField):
+    def get_c_name(self):
+        return self.name
+
+    def get_c_def(self):
+        return "typedef %s" % super(CAlias, self).get_c_def()
+        # if self.len is not None:
+        #     return "typedef %s %s[%d];" % (self.type.get_c_name(), self.name, self.len)
+        # else:
+        #     return "typedef %s %s;" % (self.type.get_c_name(), self.name)
+
+    # def needs_byte_swap
+
+
 class CStruct(Struct):
     def get_c_def(self):
         return "\n".join([
-            "typedef struct __attribute__((__packed__)) {\n%s;" % (
-                ";\n".join(["  %s" % x.get_c_def()
-                            for x in self.fields])),
+            "typedef struct __attribute__((__packed__)) {\n%s" % (
+                "\n".join(["  %s" % x.get_c_def()
+                           for x in self.fields])),
             "} %s;" % self.get_c_name()])
 
     def get_vla_assign_code(self, prefix, path):
@@ -156,7 +173,7 @@ class CSimpleType (SimpleType):
         try:
             self.get_swap_to_host_func_name()
             return True
-        except:
+        except KeyError:
             pass
         return False
 
@@ -335,8 +352,8 @@ class CMessage (Message):
         if self.has_payload():
             return "\n".join([
                 "typedef struct __attribute__ ((__packed__)) {",
-                "%s; " %
-                ";\n".join(self.payload_members),
+                "%s " %
+                "\n".join(self.payload_members),
                 "} %s;" % self.get_payload_struct_name(),
                 "",
                 "typedef struct __attribute__ ((__packed__)) {",
@@ -609,7 +626,8 @@ def emit_definition(parser, json_file, emitted, o):
         if (o not in parser.enums_by_json[json_file] and
                 o not in parser.types_by_json[json_file] and
                 o not in parser.unions_by_json[json_file] and
-                o.name not in parser.messages_by_json[json_file]):
+                o.name not in parser.messages_by_json[json_file] and
+                o not in parser.aliases_by_json[json_file]):
             return
         guard = "defined_%s" % o.get_c_name()
         print("#ifndef %s" % guard)
@@ -690,6 +708,8 @@ def gen_json_unified_header(parser, logger, j, io, name):
     emitted = []
     for e in parser.enums_by_json[j]:
         emit_definition(parser, j, emitted, e)
+    for a in parser.aliases_by_json[j]:
+        emit_definition(parser, j, emitted, a)
     for u in parser.unions_by_json[j]:
         emit_definition(parser, j, emitted, u)
     for t in parser.types_by_json[j]:
@@ -765,7 +785,8 @@ if __name__ == '__main__':
                             union_class=CUnion,
                             struct_type_class=CStructType,
                             field_class=CField,
-                            message_class=CMessage)
+                            message_class=CMessage,
+                            alias_class=CAlias)
 
     # not using the model of having separate generated header and code files
     # with generated symbols present in shared library (per discussion with
diff --git a/src/vpp-api/vapi/vapi_cpp_gen.py b/src/vpp-api/vapi/vapi_cpp_gen.py
index 6b62bc4da22..c08993dc918 100755
--- a/src/vpp-api/vapi/vapi_cpp_gen.py
+++ b/src/vpp-api/vapi/vapi_cpp_gen.py
@@ -5,7 +5,7 @@ import os
 import sys
 import logging
 from vapi_c_gen import CField, CEnum, CStruct, CSimpleType, CStructType,\
-    CMessage, json_to_c_header_name
+    CMessage, json_to_c_header_name, CAlias
 from vapi_json_parser import JsonParser
 
 
@@ -21,6 +21,10 @@ class CppEnum(CEnum):
     pass
 
 
+class CppAlias(CAlias):
+    pass
+
+
 class CppSimpleType (CSimpleType):
     pass
 
@@ -251,7 +255,8 @@ if __name__ == '__main__':
                             struct_type_class=CppStructType,
                             field_class=CppField,
                             enum_class=CppEnum,
-                            message_class=CppMessage)
+                            message_class=CppMessage,
+                            alias_class=CppAlias)
 
     gen_cpp_headers(jsonparser, logger, args.prefix, args.gen_h_prefix,
                     args.remove_path)
diff --git a/src/vpp-api/vapi/vapi_json_parser.py b/src/vpp-api/vapi/vapi_json_parser.py
index 39acca0b538..3eb5d3616e1 100644
--- a/src/vpp-api/vapi/vapi_json_parser.py
+++ b/src/vpp-api/vapi/vapi_json_parser.py
@@ -45,6 +45,10 @@ class Field(object):
         return self.is_vla() or self.type.has_vla()
 
 
+class Alias(Field):
+    pass
+
+
 class Type(object):
     def __init__(self, name):
         self.name = name
@@ -55,12 +59,6 @@ class Type(object):
 
 class SimpleType (Type):
 
-    def __init__(self, name):
-        super(SimpleType, self).__init__(name)
-
-    def __str__(self):
-        return self.name
-
     def has_vla(self):
         return False
 
@@ -290,11 +288,12 @@ class JsonParser(object):
     def __init__(self, logger, files, simple_type_class=SimpleType,
                  enum_class=Enum, union_class=Union,
                  struct_type_class=StructType, field_class=Field,
-                 message_class=Message):
+                 message_class=Message, alias_class=Alias):
         self.services = {}
         self.messages = {}
         self.enums = {}
         self.unions = {}
+        self.aliases = {}
         self.types = {
             x: simple_type_class(x) for x in [
                 'i8', 'i16', 'i32', 'i64',
@@ -310,6 +309,7 @@ class JsonParser(object):
         self.union_class = union_class
         self.struct_type_class = struct_type_class
         self.field_class = field_class
+        self.alias_class = alias_class
         self.message_class = message_class
 
         self.exceptions = []
@@ -317,6 +317,7 @@ class JsonParser(object):
         self.types_by_json = {}
         self.enums_by_json = {}
         self.unions_by_json = {}
+        self.aliases_by_json = {}
         self.messages_by_json = {}
         self.logger = logger
         for f in files:
@@ -329,6 +330,7 @@ class JsonParser(object):
         self.types_by_json[path] = []
         self.enums_by_json[path] = []
         self.unions_by_json[path] = []
+        self.aliases_by_json[path] = []
         self.messages_by_json[path] = {}
         with open(path) as f:
             j = json.load(f)
@@ -369,6 +371,19 @@ class JsonParser(object):
                     self.unions[union.name] = union
                     self.logger.debug("Parsed union: %s" % union)
                     self.unions_by_json[path].append(union)
+                for name, body in j['aliases'].iteritems():
+                    if name in self.aliases:
+                        progress = progress + 1
+                        continue
+                    if 'length' in body:
+                        array_len = body['length']
+                    else:
+                        array_len = None
+                    t = self.types[body['type']]
+                    alias = self.alias_class(name, t, array_len)
+                    self.aliases[name] = alias
+                    self.logger.debug("Parsed alias: %s" % alias)
+                    self.aliases_by_json[path].append(alias)
                 for t in j['types']:
                     if t[0] in self.types:
                         progress = progress + 1
@@ -429,12 +444,16 @@ class JsonParser(object):
             return self.enums[name]
         elif name in self.unions:
             return self.unions[name]
+        elif name in self.aliases:
+            return self.aliases[name]
         elif mundane_name in self.types:
             return self.types[mundane_name]
         elif mundane_name in self.enums:
             return self.enums[mundane_name]
         elif mundane_name in self.unions:
             return self.unions[mundane_name]
+        elif mundane_name in self.aliases:
+            return self.aliases[mundane_name]
         raise ParseError(
             "Could not find type, enum or union by magic name `%s' nor by "
             "mundane name `%s'" % (name, mundane_name))